New-style hard alloy -- exterior coating hard alloy

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Summary: Basically introduced the function of coating hard alloy, category and coating technology, a few listedder test data. Keyword: Hard alloy; Coating razor blade; 1 overview passes cutting cutting tool deposit of chemical gas phase (the method such as CVD) , in hard alloy razor blade apparently the layer such as the TiC of besmear Fu wear-resisting or TiN, HfN, Al2O3, form exterior coating hard alloy. This is the significant progress of technology of development of contemporary hard alloy. 1969, germany overcomes captive uncle company and Sweden the razor blade of TiC coating hard alloy that the company develops Shanteweike the first time throw on the market. After 1970, the United States, Japan and other country also begin to produce this kind of razor blade. Come more than 30 years, coating technology had very great progress. Razor blade of coating hard alloy already developed the 3rd generation, the 4th acting product by generation, the 2nd generation. Razor blade of coating hard alloy all is made commonly but the style of dislocation. With machine clip the method installs card to be used on arbor or cutter hub. It has the following advantage: 1) has extremely tall hardness and wearability as a result of the coating material of surface layer, reason and not photograph of coating hard alloy is compared, coating hard alloy allows to use higher cutting rate, rose to machine efficiency thereby; Or cutting tool durability can rise substantially below same cutting rate. 2) because coating material and be machined the coefficient of friction between material is lesser, reason and not photograph of coating razor blade is compared, force has the cutting of coating razor blade to be reduced certainly. When 3) coating razor blade is machined, it is better to already machined exterior quality. 4) is good as a result of integral performance, coating razor blade has better versatility. The razor blade of brand of a kind of coating has broader suitable scope. The method with the most commonly used coating of hard alloy of 2 coating craft is law of deposit of gas phase of high temperature chemistry () of abbreviation HTCVD law, it is to be in often be pressed or in the deposit system of negative pressure, wait for pure H2, CH4, N2, TiCl4, AlCl3, CO2 gas or steam, press the composition of deposit, among them concerned gas, by deserve to compare certainly mix equably, ordinal besmear arrives constant temperature (it is 1000 ℃ ~ commonly 1050 ℃ ) surface of hard alloy razor blade, be in namely TiC of bit surface deposit, TiN, Ti(C, n) or Al2O3 or their compound coating. Reaction equation generalizes as follows: TiCl4+CH4+H2 → TiC+4HCl+H2 Normal MARGIN of 28pt"> TiCl4+½N2+2H2 → : 0cm 0cm 0pt; LINE-HEIGHT: Ti(C of 28pt"> TiCl4+CH4+½N2+H2 → , n)+4HCl+H2normal > Value="2" HasSpace="False" Negative="False" NumberType="1" TCSC="0">2A1Cl3+3CO2+3H2 uses deposit of gas phase of PCVD(plasma chemistry) the law undertakes in surface of hard alloy razor blade coating also gets applied, because coating craft temperature is inferior (800 ° of 700 ° ~ ) , the scope that the bending strength of reason razor blade reduces is lesser, more appropriate to mill razor blade. Before coating, surface of matrix razor blade must be purified, ying Dun of cutting blade place is changed. After coating, because of coating material and base cease the difference of existence of linear expansion coefficient of material, surface of reason coating razor blade produces leftover tensile stress inevitably and make bit bending strength is reduced. Besmear first with TiC layer normally in matrix apparently, because the linear expansion coefficient of TiC and base material are the most adjacent; Besmear again outside TiN, Al2O3. In the past, only coat material all uses TiC, material of double deck coating is multi-purpose TiC/TiN, TiC/Al2O3, three-layer coating material is multi-purpose TiC/Ti(C, n)/TiN, Tic/Al2O3/TiN. In recent years, as the improvement of base material, coating data is useful also TiN pays a copy, namely the coating material such as TiN/TiC/TiN still has HfN, MoS2 to wait. Home of circumstance of hard alloy of coating of 3 home development studies technology of coating of hard alloy CVD develops bit, from 70 time began first, but form productivity truly and extend application or the issue of 80 time in great quantities. 1983, individual plant continent hard alloy factory introduced HTCVD coating furnace and essence to grind from Swiss Bernex company, the equipment of form a complete set such as point passivation, produced the razor blade of coating hard alloy of CN series and CA series, matrix razor blade uses homebred name (1) seeing a table. Later, this factory introduced equipment and coating technology from Swedish Sandvik company again, produced razor blade of hard alloy of YB series coating, matrix uses special and special data (watch 2) . Among them YB120, YB320 is milling brand, other and main use at turning treatment. From tribute hard alloy factory introduces the country such as the United States coating equipment, the product of razor blade of coating hard alloy that also has ZC series (express 3) . In recent years, from tribute hard alloy factory rolled out a brand to be the coating razor blade of ZC21. Its matrix is the stuff that has gradient structure, coating material is TiC/TiN, density is 13.

0 ~ 14.

0g/cm3, bending strength ≥ 1.

6GPa, can use at discontinuous cutting, yi Ke is used at successive cutting. Because limits of application of cutting tool of 4 coating hard alloy passes coating technology, the tenacity of matrix razor blade and bending strength drop inevitably somewhat, add the account such as the chemistry of coating material, razor blade of reason coating hard alloy still has certain suitable scope only. It can be used at steel of all sorts of carbolic element structure, alloy structure steel (include qualitative state of normalizing and attune) , the rough machining of the precision work that cuts stainless steel of steel, tool steel, martensite and casting pig easily, semifinishing machining and smaller negative charge. Coating razor blade most apply to successive turning, but the Yi Ke in cutting the profile modeling turning with profound not big change, discontinuous turning with not quite big wallop and certain milling working procedure is used. Be in in recent years cut off, coating bit already also was used in car whorl. But, tiC and TiN coating razor blade are unsuited at processing following data: Stainless steel of high temperature alloy, titanium alloy, austenite, nonferrous metal (the pure metal such as copper, nickel, aluminous, zinc and its alloy) . Heavy rough machining, the surface has serious mix arenaceous also should not be with the treatment of crustaceous cast use coating razor blade. Surface of razor blade of hard alloy of coating of 5 cutting experiment has TiC, TiN, Ti(C, the layer with the very tall hardness such as N) , Al2O3, reason wearability is extremely strong: The WC that the author ever used coating of monolayer of HTCVD law TiC base the YW1/TiC that hard alloy razor blade is matrix, with not the WC of coating base YN05 of alloy of alloy YT15, YT30+TaC, TiC radical, undertake turning contrasts. Workpiece material pledges for 60Si2Mn(wither high strenth steel, HRC40) , p =0 of cutting dosage α .

5mm, f=0.

2mm/r, ν =115m/min. ° of 0=4 of γ of parameter of cutting tool geometry, α 0=8 ° , ° of κ R =45, ° of λ S =-4, RE =0.

8mm. Measure lathe tool respectively hind knife face wears away VB and before knife face crescent moon wears away depression KT, if gotten cutting tool wear curve pursues 1, the graph is shown 2 times. Can see, the wearability of YW1/TiC coating razor blade not only outclass YT15(P10) , and also prep above YT30+TaC, (P01) , return prep above even YN05(P01) of TiC radical alloy; And fight ability of wear-resisting of crescent moon depression tatty particularly remarkable. The author is matrix with razor blade of YW3 hard alloy again, in the HTCVD coating furnace of some academy, the coating material of the monolayer on besmear, double deck, three-layer, form razor blade of 3 kinds of coating; YW3/TiC, YW3/TiC/TiN, YW3/TiC/Ti(C, n)/TiN. YW3 of hard alloy of along with matrix, together turning 60Si2Mn steel (HRC40) . P =0 of cutting dosage α .

5mm, f=0.

2MM/r, ν =150m/min, ° of 0=4 of γ of parameter of cutting tool geometry, α 0=8 ° , ° of κ R =45, ° of λ S =4, RE =0.

8mm. Of earning hind wear curve sees knife face graph 3. The wearability outclass of coating razor blade not YW3 of coating razor blade; The coating razor blade of different number of plies, its wearability also has certain difference, of besmear three-layer banner, the take second place of Tu Er layer. Of besmear monolayer more take second place, but the difference is not too big. The author enrages photograph deposit with PVD(physics again) coating craft, in TiC of Fu of the besmear on matrix of razor blade of YT15(P10) hard alloy, next turning 60Si2Mn steel (HRC40) , undertake with YT15 razor blade turning contrasts. P =1mm of cutting dosage α , f=0.

2mm/r, ν =115m/min. ° of 0=4 of γ of parameter of cutting tool geometry, α 0=8 ° , ° of κ R =45, λ S=4 ° , RE =0.

8mm. Of earning hind wear curve sees knife face graph 4. Can see, the use effect Yi Jia of razor blade of PVD coating hard alloy. PVD coating temperature is low, be helpful for reducing the exterior remains stress of razor blade of hard alloy coating; But the combinative strength between PVD coating and matrix inferiors a bit at CVD craft. As the progress of PVD technique, application is wide with each passing day already in recent years. The cutting force of coating razor blade is less than not coating razor blade, because of the knife, the coefficient of friction between bits is reduced. The experiment makes clear, p kind horniness razor blade cuts steel after besmear TiC, advocate cutting force Fc can reduce 4 % of 3 % ~ about (with not coating razor blade compares) , besmear TiN or TiC/TiN, advocate cutting force Fc can reduce 6 % ~ about 9 % . Of Fp and Ff reduce particularly remarkable. The effect that Al2O3 coating reduces to cutting force and TiN coating are adjacent. CNC Milling